The Midnight Sun
The Midnight Sun glows in our sky from the 27th of May until the 14th of July. During this period, it never slides below the horizon. The sun is at its lowest at the time 00:40. So the sun is up continuously for 47 days at Kiruna's latitude. The periods prior to and following that of the Midnight Sun are also very bright. This is why we usually talk about having 100 days without night.